The invention relates to a centrifuge for separating solids/liquids mixtures in which at least one concentrated solids phase is at least partially discharged through at least one aperture arranged below the liquid level in the jacket of the drum and which exhibits at least one control device for opening or closing this aperture.
A known centrifuge of this type has nozzles on the circumference of the drum with control devices for opening or closing these nozzles. The control devices are automatically functioning valves which can be actuated by the pressure in the concentrated solids phase and permit automatic bleeding of the solids phase from the centrifuge. See German AS No. 1,482,708 incorporated herein by reference.
It is a disadvantage if the control devices are designed in valve-like fashion and consist of complicated fine-mechanical parts constructed with great precision whose sensitivity and susceptibility to disruption is not suitable for the rugged operation of a centrifuge.
In particular, it can not be guaranteed that the valves distributed over the circumference suddenly open at the same time. If this does not occur, however, the centrifuge is brought out of balance due to the one-sided discharge, which can lead to considerable disruptions including damage to the machine.
Another known solid-bowl centrifuge (German AS No. 2,063,063 corresponding to U.S. Pat. No. 3,836,070 incorporated herein by reference) with slurry discharge apertures in the jacket, has means for opening and closing these apertures which are actuated by use of a jolt-like deceleration or acceleration of the centrifuge. In this known centrifuge, the complicated and involved mechanism for opening and closing the slurry discharge apertures is likewise a disadvantage. Even more questionable, however, are the deceleration or acceleration jerks required for actuation of the control devices, the employment of such jerks being practically prohibitive, particularly given larger machines with accordingly higher forces of gravity. Of course, this technique also has a disadvantageous influence on the machine itself as well as its contents.